Phytoliriomyza suetsugui Kato, 2022

Kato, Makoto, Yamamori, Luna & Imada, Yume, 2022, Diversity underfoot of agromyzids (Agromyzidae, Diptera) mining thalli of liverworts and hornworts, ZooKeys 1133, pp. 1-164 : 1

33. Phytoliriomyza suetsugui Kato sp. nov.

Fig. 62

Material examined.

Holotype: Japan: 1♂ (MK-AG-a221), Arakawa, Takae, Higashi-son, Okinawa Pref. (26.6655°N, 128.2542°E, 45 m asl), 22-II-2011 (as larva on Conocephalum orientalis collected by K. Suetsugu), emerged on 16-IV-2011, NSMT-I-Dip 32085. Paratypes: Japan: 2♂1♀ (MK-AG-a433, a434, 698), same data as holotype emerged on 14-22-IV-2011, NSMT-I-Dip 32086-32088; 1♀ (MK-AG-766), Naon, Yamato, Oshima, Kagoshima Pref., 12-XII-2014 (as larva), emerged on 17-III-2015, NSMT-I-Dip 32089; 1♀ (MK-AG-761), Mt. Yonaha, Kunigami, Okinawa Pref., 18-VII-2016 (as larva on C. orientalis ), emerged on 14-X-2016, NSMT-I-Dip 32090.

Other material.

Japan: 3♂3♀, Arakawa, higashi-son, Okinawa Pref., 10-XI-2021 (as larva on C. orientalis ), emerged on 27-I-12-II-2022.

Diagnosis.

A small dark species (wing length 1.3-1.5 mm) having a pruinose dark gray scutum and scutellum, a black 1st flagellomere, dark maxillary palpus, dark halteres, and brown legs. Male epandrium inner-laterally with a tubercle like seta, and inner-basally with a comb comprising six long fused tubercle-like setae. Larva mines the thallus of Conocephalum orientalis .

Description.

Adult male (Fig. 62A-D ).

Head: Head light yellow, with ocellar tubercle brown, back of head dark brown (Fig. 62C ). Antenna porrect, first flagellomere dark brown, pedicel and scape brown (Fig. 62B ). Arista subbasal, black, pubescent. Clypeus, face, gena, parafacial and postgena yellow. Proboscis normal, yellow; palpus brown, cylindrical (Fig. 62C ). Chaetotaxy: Front orbitals three pairs; one ori directed inward; two ors directed upward (Fig. 62B ). Orbital setulae minute and erect, in a single row.

Thorax: Thorax pruinose. Scutum and scutellum pruinose gray (Fig. 62D ). Subscutellum light yellow except for brown posterior half. Mediotergite and anatergite brown, katatergite light yellow (Fig. 62B ). Pleuron yellow light yellow with brownish patches on venter of propleuron, anepisternum, katepisternum, anepimeron, and meron. Haltere brown. Calypter margin and hairs gray. Leg segments brownish, basal half of femur paler (Fig. 62A ). Chaetotaxy: Scutum with 1+3 dorsocentrals, shortened anteriorly (Fig. 62D ). Acrostichal setulae five or six pairs in two irregular rows. Wing: Wing length 1.3 mm, costa reaching M1 (Fig. 62A ). Length of ultimate section of vein M4 divided by penultimate section 1.3.

Abdomen: Abdomen dorsally subshiny brown; epandrium dark brown (Fig. 62B ). Genitalia: (Fig. 62I-L ) Epandrium rounded apically; inner-lateral surface with a long tubercle-like seta; inner-anterior surface with a comb comprising six fused long tubercle-like setae; inner-basal margin with a row of six or seven small tubercle-like setae (Fig. 62I, K ). Surstylus rounded, curved inwards, setose apically, with one long tubercle-like seta on posterior subdistal margin (Fig. 62K ). Cercus narrow, setose. Subepandrial sclerite H-shaped. Hypandrium slightly sclerotized along outer margin (Fig. 62I ). Postgonite bare, goose barnacle-shaped, rounded apically (Fig. 62I ). Phallophorus with deep incision below, articulated with phallapodeme, fused to epiphallus (Fig. 62J ). Basiphallus with a plate-like sclerite on left side (Fig. 62J ). Hypophallus broad, membranous covered with microtrichia ventrally; lateral margins lightly sclerotized; medially with a pair of fused, narrow ventrally incurved sclerites; laterally with a pair of converging narrow sclerites (Fig. 62J ). Paraphallus pale membranous; paraphalli spread laterally, jointed basally (Fig. 62J ). Mesophallus dark, cylindrical, widest subbasally, 4/5 as long as distiphallus (Fig. 62J ). Distiphallus comprising one pair of stout tubules basally parallel to each other; covered by a transparent membrane with a pair of 7 oval minute sclerites; basal half composed of ventral dark subtriangular sclerite and weaker medial region; distal half cylindrical, dorsally pigmented, widening toward truncated unpigmented apex (Fig. 62J ). Ejaculatory apodeme pale brown, with fan-shaped blade and long stalk; base wide to one side; sperm pump clear (Fig. 62L ).

Female (Fig. 62E-H ). Similar to male, but slightly larger; frons and pleuron darker. Wing length 1.5 mm. Postabdomen: (Fig. 62M, N ) Oviscape dark brown, setigerous (Fig. 62M ). Tergite 10 cruciform, laterally uniting narrow pleural sclerites (Fig. 62N ). Each cercus with two stout, apical, trichoid sensilla, ½ length of cercus (Fig. 62N ). Spermathecae semi-orbicular, with truncate proximal ends (Fig. 62M ).

Etymology.

The specific name honors a botanist, Dr. Kenji Suetsugu, who collected thalli of Conocephalum orientalis . at the type locality.

Japanese name.

Yanbaru-jagoke-hamoguribae.

Host plant.

Conocephalum orientalis .

Mine.

(Fig. 62Q ) Larvae construct linear mines in the midrib of the thallus, and pupate in the mines.

Biological notes.

The habitats of this species are stream banks in warm temperate evergreen forests dominated by Castanopsis sieboldii (Fig. 62O, P ).

Distribution.

Japan: Amami and Okinawa Islands (Fig. 61 ).

Remarks.

This species resembles P. ricciae in having a wholly dark scutum, yellow pedicel and scape of the antenna, and dark maxillary palpus; it is distinguished from the latter by the presence of a comb of tubercle-like setae on the male epandrium. This species also resembles P. marchantiae , P. rebouliae , P. lanternaria , and P. conocephali in having dark scutum and a comb comprising 5-8 tubercle-like setae on the male epandrium; it is distinguished from them by lacking a small yellow mark on both the scutellum and the posterior margin of the scutum.

Species associated with Riccia

Figures

Figure 61. Locality records of three Phytoliriomyza species associated with Conocephalum spp.: P. conocephali and P. suetsugui.

Figure 62. Phytoliriomyza suetsugui sp. nov. A-D holotype male A habitus B lateral C frontal D dorsal E-H paratype female (MK-AG-a 434) E dorsal F frontal G lateral H posterior I-L male genitalia I whole genitalia, ventral J phallic complex, lateral K epandrium, ventral L ejaculatory apodeme M, N female postabdomen M oviscape and spermatheca N tergite 10 O, P habitat at type locality Q mined thallus of Conocephalum orientalis.